Just for teh lulz. XD Both of these are from Mugglenet. Oh yeah, and spoilers.

25 Ways to Annoy Dolores Umbridge

Guaranteed to get you a date with some some kittens and a bottle of Veritaserum.

1. Offer her flies. Tell her they're good with ketchup.
2. Ask her if she's related to Trevor.
3. Follow close behind her all day, making clip-clopping noises with your tongue.
4. Ask her if she's met the handsome new divination teacher.
5. Tell her that Cornelius Fudge only hired her to scare small children.
6. Dye all her clothes black.
7. ...when she acts horrified, say you were only trying to help her, and that "black is the new pink."
8. Send her love notes, signing them as if they were from Cornelius Fudge.
9. Perpetually use the word "umbrage."
10. Remind her constantly that her "Selwyn Family Heirloom" contained the shreds of the most evil wizard of modern times.
11. Create your own Educational Decrees to contradict her's.
12. Make sure these said Decrees are identical to her own. Post them everywhere.
13. Turn all of her kittens into toads.
14. Talk in stage whispers about "army meetings," "Dumbledore," and "Harry Potter." Should she confront you, stop talking, smile, and whistle innocently.
15. Tell her you're doing a Herbology project and want to know more about the plants in her natural habitat.
16. Buy her Weasleys' Wild-Fire Whiz-Bangs for Christmas.
17. Ask her if she's read the latest edition of the Quibbler. When she says no, offer her one.
18. When she's within earshot, announce loudly that Snape was a better headmaster than she was.
19. Or if you're feeling particularly daring, announce that Sir Cadogan would make a better headmaster.
20.Offer her a free membership with S.P.E.W.
21. Tell her that you didn't do your homework because "progress for progress sake must be prohibited."
22. Ask her if she wears that mask all the time, or just when she's teaching.
23. Ponder loudly whether the title "Hogwarts High Inquisitor" sounds quite as powerful as, say, "Muggle Prime Minister."
24. Present her with a voodoo doll with an uncanny resemblance to her, but just before giving it to her, stash it away, muttering, "Oops, that one's Harry's..."
25. Buy her a pet Niffler.

23 Things To Do in a Ministry of Magic Elevator

Guaranteed to, er..get you admitted to St. Mungo's?

1. When there's only one other person in the elevator, tap them on the shoulder and then pretend it wasn't you.
2. Push the buttons and pretend they jinx you. Wait for the effects of the 'jinx' to wear off, smile, and go back for more.
3. Ask if you can push the button for other people, but intentionally push the wrong ones.
4. Hold the doors open and say you're waiting for a friend. After a while let the doors close and say, "Hi Greg. How's your day been?"
5. Drop a quill and wait until someone goes to pick it up and then scream, "That's mine!"
6. Bring a camera and take pictures of everyone in the elevator.
7. Move your desk into the elevator and whenever anyone gets on ask if they have an appointment.
8. Lay down a Muggle Twister mat and ask people if they would like to play.
9. Randomly ask "Did you feel that?" When they look at you curiously, begin to explain your theory that a troll has made its way into the building, become more panicked by the minute.
10. Stand really close to someone, sniffing them occasionally. As they are getting off, tell them you "know of a potion that can cure thatů"
11. When the doors close, announce to the others in a voice of forced calm, "It's okay, don't panic, they open again!"
12. Swat at flying memos which don't exist.
13. Call out, "Group hug!" and then enforce it. Use Imperius if necessary.
14. Grimace painfully while smacking your forehead and muttering, "Shut up, all of you, just shut up!" Then explain that the Legilimency lessons are working a little too well.
15. Crack open your briefcase or purse and peer inside periodically while whispering, "Got enough air in there?"
16. Stand silently and motionless in the corner facing the wall, without getting off. If someone approaches you, turn around and try to bite them.
17. Stare at another passenger for a while and then announce in horror, "You're one of THEM!" and back away slowly.
18. Charm one of your fingers to talk and use it to communicate with other passengers.
19. Listen to the elevator walls with your Extendable Ears.
20. Speak incantations when anyone presses a button. (Alohomora, for example)
21. Stare manically and grin at another passenger for an extended amount of time before announcing, "I have new socks on."
22. Draw a little square on the floor with your wand and announce to the other passengers in an unnecessarily loud voice, "This is MY personal space!"
23. If anyone questions any of your actions, claim to be under the influence of dark magic.